PARK WATCH Article March 2023 |

Dozens of people took part in our latest sea slug census under the San Remo Bridge, lead by Kade Mills, ReefWatch Coordinator

‘I have waited 55 years to see one!’ was the cry from one participant as a sea slug was pointed out to her at ReefWatch’s recent San Remo Sea Slug Census.

Her son (squatted over a rockpool) then points and asks ‘Is this one of those things you wanted to see’. Much to his mother’s chagrin, at 16 he had found his own within ten minutes of walking out onto the intertidal area under the San Remo Bridge. Phew, the hardest part of running a Sea Slug Census event – finding a sea slug – was achieved!

Sea slugs is not a scientific term nor is it a particularly flattering title when used to describe these tiny gastropods (snails). Upon hearing or reading the word ‘slug’ your mind likely conjures up an image of a drab grey elongated blob that slimes its way around the garden. As you can see on these pages this is a far cry from what we find in Victoria’s marine environment.

Caption: A selection of the many sea slugs sighted on the day. All images Kade Mills.

To help participants find sea slugs they were briefed to ‘think like a slug, to find a slug’ this meant searching out dark cool places with plenty of water. This kept participants on the firm ground under the bridge to reduce trampling as it was darker and cooler in the shade of the bridge. Travelling up to two hours for the chance to see a sea slug by the San Remo seashore, over 70 people of all ages immersed themselves in the pleasure and meditative quality of focussing all of your energies into searching for these elusive critters.

Many slugs (most of them colourful) were found across the two days of searching under the bridge at San Remo. Many more were found by the author and one of Victoria’s top nudibranch spotters, Nick Shaw, on a night snorkel at the same location. Night snorkelling and rock pool rambling is an incredible way to observe many of marine species, especially nudibranchs which are more active after the sun goes down.

The highlight of the event, aside from the enthusiasm and care taken by all the kids, was watching people’s perception change as they developed a new-found appreciated for this intertidal area which is often derogatorily referred to as ‘just a mudflat’. Because this ain’t no ordinary ‘mudflat’.

The San Remo Marine Community is an extensive reef and seagrass flat to the north of San Remo Bridge. It has a unique combination of physical attributes that are not found elsewhere in Victoria (northerly aspect, adjacent to fast flowing channel, low wave energy and made of pitted basalt rarely found in intertidal areas).

However, it is the diverse array of marine invertebrates in particular the sea slugs that make this place so special. Over 120 species have been recorded from the area. That is approximately 25 per cent of the known southern Australia species and over five per cent of the world’s!

Community helped get the site formally protected in 1991 after fighting off a proposed marina.

Damage from boats, sedimentation, and coastal development are on-going threats to the bay. We’ll continue to run citizen science events and document sea slugs in San Remo and work on achieving our Western Port Bay framework.

This event was funded by Coastcare as a part of Summer by The Sea.

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